24p questions

Chris Hurd · February 26th, 2005, 01:05 PM

Unless you're intending to transfer your video to 35mm film, I would recommend shooting in the basic 24P mode, with 2:3 pulldown. The "advanced" 2:3:3:2 option is better suited for 35mm film transfer, but is not ideal for distributing on video.

That said, any number of other factors could be contributing to your problem. Don't shoot in the Green Box (easy recording) program mode, and make sure you have Gain set to +0db and not Auto. Other considerations are your shutter speed and any Custom Presets you're using. Welcome to DV Info Net,

Andrew Oh · February 26th, 2005, 01:14 PM

Also, do you mean noise or aliasing on edges? If that's what you mean, you may want to turn down the sharpness a bit.

Michael Galvan · February 26th, 2005, 07:25 PM

Hi Scot,

I don't know about Avid as I work with Final Cut Pro, but I would recommend always shooting in 2:3:3:2 as it gives you more options than regular 3:2 pulldown. True, 3:2 pulldown allows you to edit on a 29.97 timeline and is meant for final viewing on NTSC but by using 2:3:3:2, you can revert the footage back to true 23.98fps and edit in that timeline. When finished with your edit, you can simply reapply the 3:2 pulldown to conform it back to 29.97 NTSC or make a progressive scan DVD.

As for your footage, check all obvious things like gain and iris levels. It could also be due to your multiple exporting ... make sure you use the appropriate DV codecs throughout your conversions.

Hope this helps,

Richard Hunter · February 26th, 2005, 08:51 PM

Hi Scot. When you shoot in progressive scan mode, and then view the results on an interlaced monitor, you will often see flickering of the fine details. You can try setting the Vertical Detail to Low (in custom preset) to reduce this effect.

Richard

Scot Hampton · February 26th, 2005, 08:58 PM

Thanks Richard, Chris and Michael...I've been reviewing some of Adam Wilts materials on the subject...and I found some really good help files (pdfs) on 24p.com.

I think the problem was the interlaced monitor, as well as perhaps my gain settings, I think i had them set on auto for my prelim tests...Am going to go back next week and do some more thorough tests, with better settings.

Joseph Andolina · February 28th, 2005, 08:11 PM

Where do I find the PDF files by Adam Wilts?

Any help would be appreciated.

Chris Hurd · February 28th, 2005, 08:23 PM

Two separate things...

Adam Wilt (a DV guru) is at www.adamwilt.com.

Various 24P docs in PDF format are at www.24p.com.

Hope this helps,

Nico van Tonder · March 1st, 2005, 04:47 AM

Hi Scott,

I am shooting with a PAL XL2 and in the beginning I had bugs crawling all over my footage - to such an extend that I thought something was wrong with the XL2. I removed the UV filter, etc., but nothing helped.

I captured the footage on an old Compaq laptop while I was building a proper XT PC.

I gave that laptop to my grandson and bought a new HP Compaq nw800 Mobile Workstation with much faster RAM and a very fast 60GB hard drive - and quess what? The bugs dissapeared like magic.

I'm not saying that is your problem - but the PC plays a very important role when capturing. Ask me!!

Alvaro Duran · March 24th, 2005, 10:31 PM

Hello everyone

I read this info in one of yoir messages:

If I have 60i, 16:9 Mode, 1/60th second shutter speed, 0db Gain the effective ASA of the XL2 is 400.

Considering this info may I assume that 24p, 16:9, 1/24th shutter speed, 0db gain is equal to an effective ISO of 160?

Mike Minor · April 2nd, 2005, 08:23 PM

Hello. When looking at some footage i shot on FCP (and also when i export it to DVD and watch it on a tv) i notice a lot of "motion lines" for lack of a better term. When theres moving on screen little lines occur around whatevers moving. Anyone experienced this/know a fix? thanks.

if you guys dont know what i'm talking about, i could post a short clip if need be.

Douglas Robbins · April 3rd, 2005, 02:06 AM

You will only see them in the browser and the viewer. They go away when you export the project.

Douglas

Richard Hunter · April 3rd, 2005, 02:56 AM

Hi Mike. I'm not sure whether you are seeing motion blur due to slow shutter or some other effect. Posting a sample clip would be the best bet.

Richard

Rob Lohman · April 3rd, 2005, 03:16 AM

Hello Alvaro, welcome aboard DVInfo.net!

ISO is very difficult "thing" in the world of digital video. You cannot
really compare it to film. I have no idea if your numbers are sound
or not. May I ask why you would need the ISO info?

Mike Minor · April 3rd, 2005, 04:12 AM

Hey, they still existed when I exported them...so i uploaded a VERY short clip to show what i'm dealing with. It's short, but its full resolution so you can see the lines around any motion.

www.sodesune.com/sample.mov

A. J. deLange · April 3rd, 2005, 08:10 AM

When you shoot 24p the camera takes 24 complete pictures per second and splits each into two fields. Calling the fields from the first picture A and A', from the second B and B' and so on the camera writes them to tape as AA' BB' B'C CC' DD' EE' FF' F'G GG' HH' and so on if 2:3:3:2 pulldown is selected. If 2:3 pulldown is selected the sequence is AA' BB' B'C CD' D'D EE' FF' FG. Each pair defines a TV frame with the two fields as given by the letters. Thus in 2:3:3:2 the first and second frames as seen on the TV are composed of the two fields from the first and second pictures taken by the camera but the third has its first field taken from picture B and its second from picture C. The next four frames are "pure" but the fifth is mixed and so on. Thus in 2:3:3:2 every 5th frame is a combination of fields from 2 different pictures. If you look at this on a progressive device (such as a computer monitor) you are shown both fields simultaneously with two pictures superposed in the mixed frames and that is what you are seeing except that in the sequence you posted you have 2 pure frames followed by 2 mixed. This, as the second sequence above shows, is to be expected with 2:3 pulldown which is what I assume you used.

The way around this problem is to shoot 30p. Only use 24p if you are definitely going to film and then use 2:3:3:2 pulldown because, as you can see from the sequences above, the individual original frames are easily recovered from 2:3:3:2 whereas they are not from 2:3. If you feel you must shoot 24p (I think the biggest beneficiaries of 24p are Canon's marketing department) then use 2:3:3:2 because only 1 in 5 frames is mixed as opposed to 2 in 4. Another solution is to view the footage on an interlaced monitor.

At http://homepage.mac.com/ajdel/FileSharing7.html you can download a sequence, "Fan" illustrating the points made above. Be sure to set high quality mode if viewing with QT (because if you dont only half the fields are shown) and look at the clip on both a computer monitor and an interlaced monitor if you possibly can. Step through 1 frame at a time to see what's happening.

February 26th, 2005, 01:05 PM	#166
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Unless you're intending to transfer your video to 35mm film, I would recommend shooting in the basic 24P mode, with 2:3 pulldown. The "advanced" 2:3:3:2 option is better suited for 35mm film transfer, but is not ideal for distributing on video. That said, any number of other factors could be contributing to your problem. Don't shoot in the Green Box (easy recording) program mode, and make sure you have Gain set to +0db and not Auto. Other considerations are your shutter speed and any Custom Presets you're using. Welcome to DV Info Net, __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

February 26th, 2005, 07:25 PM	#168
Michael Galvan Major Player Join Date: Sep 2004 Location: New York, NY Posts: 775	Hi Scot, I don't know about Avid as I work with Final Cut Pro, but I would recommend always shooting in 2:3:3:2 as it gives you more options than regular 3:2 pulldown. True, 3:2 pulldown allows you to edit on a 29.97 timeline and is meant for final viewing on NTSC but by using 2:3:3:2, you can revert the footage back to true 23.98fps and edit in that timeline. When finished with your edit, you can simply reapply the 3:2 pulldown to conform it back to 29.97 NTSC or make a progressive scan DVD. As for your footage, check all obvious things like gain and iris levels. It could also be due to your multiple exporting ... make sure you use the appropriate DV codecs throughout your conversions. Hope this helps, __________________ www.michaelgalvan.com www.screenanthology.com

February 28th, 2005, 08:11 PM	#171
Joseph Andolina Regular Crew Join Date: Mar 2004 Location: Everett, WA Posts: 178	Adam Wilts Where do I find the PDF files by Adam Wilts? Any help would be appreciated.

February 28th, 2005, 08:23 PM	#172
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Two separate things... Adam Wilt (a DV guru) is at www.adamwilt.com. Various 24P docs in PDF format are at www.24p.com. Hope this helps, __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

March 1st, 2005, 04:47 AM	#173
Nico van Tonder Regular Crew Join Date: Oct 2004 Location: Pretoria, South Africa Posts: 33	Hi Scott, I am shooting with a PAL XL2 and in the beginning I had bugs crawling all over my footage - to such an extend that I thought something was wrong with the XL2. I removed the UV filter, etc., but nothing helped. I captured the footage on an old Compaq laptop while I was building a proper XT PC. I gave that laptop to my grandson and bought a new HP Compaq nw800 Mobile Workstation with much faster RAM and a very fast 60GB hard drive - and quess what? The bugs dissapeared like magic. I'm not saying that is your problem - but the PC plays a very important role when capturing. Ask me!! __________________ Nico

February 26th, 2005, 01:14 PM	#167
Andrew Oh Regular Crew Join Date: Jan 2005 Location: Los Angeles, CA Posts: 86	Also, do you mean noise or aliasing on edges? If that's what you mean, you may want to turn down the sharpness a bit.

February 26th, 2005, 08:51 PM	#169
Richard Hunter Trustee Join Date: Dec 2004 Location: Lipa City Batangas, Philippines Posts: 1,110	Hi Scot. When you shoot in progressive scan mode, and then view the results on an interlaced monitor, you will often see flickering of the fine details. You can try setting the Vertical Detail to Low (in custom preset) to reduce this effect. Richard

February 26th, 2005, 08:58 PM	#170
Scot Hampton Tourist Join Date: Feb 2005 Location: Washington, DC Posts: 4	Thanks Richard, Chris and Michael...I've been reviewing some of Adam Wilts materials on the subject...and I found some really good help files (pdfs) on 24p.com. I think the problem was the interlaced monitor, as well as perhaps my gain settings, I think i had them set on auto for my prelim tests...Am going to go back next week and do some more thorough tests, with better settings.

March 24th, 2005, 10:31 PM	#174
Alvaro Duran Tourist Join Date: Mar 2005 Location: Quitp-Ecuador-Southamerica Posts: 1	XL2 ISO value at 24p Hello everyone I read this info in one of yoir messages: If I have 60i, 16:9 Mode, 1/60th second shutter speed, 0db Gain the effective ASA of the XL2 is 400. Considering this info may I assume that 24p, 16:9, 1/24th shutter speed, 0db gain is equal to an effective ISO of 160?

April 2nd, 2005, 08:23 PM	#175
Mike Minor Regular Crew Join Date: Dec 2004 Posts: 32	Motion lines on 24p 16:9 Footage Hello. When looking at some footage i shot on FCP (and also when i export it to DVD and watch it on a tv) i notice a lot of "motion lines" for lack of a better term. When theres moving on screen little lines occur around whatevers moving. Anyone experienced this/know a fix? thanks. if you guys dont know what i'm talking about, i could post a short clip if need be.

April 3rd, 2005, 02:06 AM	#176
Douglas Robbins Regular Crew Join Date: Sep 2004 Location: san bruno, ca Posts: 60	You will only see them in the browser and the viewer. They go away when you export the project. Douglas

April 3rd, 2005, 02:56 AM	#177
Richard Hunter Trustee Join Date: Dec 2004 Location: Lipa City Batangas, Philippines Posts: 1,110	Hi Mike. I'm not sure whether you are seeing motion blur due to slow shutter or some other effect. Posting a sample clip would be the best bet. Richard

April 3rd, 2005, 03:16 AM	#178
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	Hello Alvaro, welcome aboard DVInfo.net! ISO is very difficult "thing" in the world of digital video. You cannot really compare it to film. I have no idea if your numbers are sound or not. May I ask why you would need the ISO info? __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

April 3rd, 2005, 04:12 AM	#179
Mike Minor Regular Crew Join Date: Dec 2004 Posts: 32	Hey, they still existed when I exported them...so i uploaded a VERY short clip to show what i'm dealing with. It's short, but its full resolution so you can see the lines around any motion. www.sodesune.com/sample.mov

April 3rd, 2005, 08:10 AM	#180
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	When you shoot 24p the camera takes 24 complete pictures per second and splits each into two fields. Calling the fields from the first picture A and A', from the second B and B' and so on the camera writes them to tape as AA' BB' B'C CC' DD' EE' FF' F'G GG' HH' and so on if 2:3:3:2 pulldown is selected. If 2:3 pulldown is selected the sequence is AA' BB' B'C CD' D'D EE' FF' FG. Each pair defines a TV frame with the two fields as given by the letters. Thus in 2:3:3:2 the first and second frames as seen on the TV are composed of the two fields from the first and second pictures taken by the camera but the third has its first field taken from picture B and its second from picture C. The next four frames are "pure" but the fifth is mixed and so on. Thus in 2:3:3:2 every 5th frame is a combination of fields from 2 different pictures. If you look at this on a progressive device (such as a computer monitor) you are shown both fields simultaneously with two pictures superposed in the mixed frames and that is what you are seeing except that in the sequence you posted you have 2 pure frames followed by 2 mixed. This, as the second sequence above shows, is to be expected with 2:3 pulldown which is what I assume you used. The way around this problem is to shoot 30p. Only use 24p if you are definitely going to film and then use 2:3:3:2 pulldown because, as you can see from the sequences above, the individual original frames are easily recovered from 2:3:3:2 whereas they are not from 2:3. If you feel you must shoot 24p (I think the biggest beneficiaries of 24p are Canon's marketing department) then use 2:3:3:2 because only 1 in 5 frames is mixed as opposed to 2 in 4. Another solution is to view the footage on an interlaced monitor. At http://homepage.mac.com/ajdel/FileSharing7.html you can download a sequence, "Fan" illustrating the points made above. Be sure to set high quality mode if viewing with QT (because if you dont only half the fields are shown) and look at the clip on both a computer monitor and an interlaced monitor if you possibly can. Step through 1 frame at a time to see what's happening.